In a weaving machine, in order to form the shed, the edge pieces of the healdframes move in guides, either on the outer or on the inner surfaces. The decreasing depth of the harness system involves decreasing the thickness of the healdframes. It becomes very difficult to ensure a sufficiently strong, and at the same time disassemblable, connection of the heald rods with the edge pieces, which is indispensable for obtaining high rigidity and long service life of the healdframe as a whole, at the high frequencies experienced in non-orthodox weaving machines.
Prior art healdframes exist in which a disassemblable connection of a heald rod with an edge piece is made by means of connecting means and screws passing toward the heald rod through holes in the edge pieces. This type of connection of the heald rod with the edge piece impairs the profile of the healdframe edge piece, as a result of the holes, and reduces the strength and rigidity of the healdframe proper.
In other known healdframes, the fixed connection is provided by a protrusion on the edge piece which is inserted into the hollow area of the healdframe heald rod, and by coupling means situated chiefly in the heald rod proper. Such connections of the heald rod and the edge piece are as a rule complicated and consist of a plurality of coupling means.
Examples of conventional means of connecting an edge piece to a healdframe are disclosed in U.S. Pat. No. 4,883,095 issued Nov. 28, 1989; and EP 0 328 953 A1 published Aug. 23, 1989, the disclosures of which are expressly incorporated by reference herein.